As I work for the team that develops reusable components for the whole organization, I found some of these issues and their solutions while using ASP.Net Ajax, jQuery,Telerik Controls and jQuery Tools.
First of all, using Telerik control “RadScriptManager” you can add jQuery as they provide a default implementation of jQuery,
Now the setup was something like this and I am sure it is a kind of trivial setup that you may find almost everywhere. So, in this case, using RadScriptManager I was adding jQuery after that using following line
var jQuery = window.jQuery = window.$ = $telerik.$;
I was restoring $ as default jQuery as alias, telerik controls change the alias and make it as $telerik.$.
After that I was adding bunch of other plug ins to jQuery using a separate file.Now in the page, I was adding jQuery Tools using there cdn link “http://cdn.jquerytools.org/1.1.2/jquery.tools.min.js”. Now the tricky part is that cdn link also contains jQuery.So, it removed all the plug ins I had and now I have $ pointing back again to jQuery, But without any plug ins.
So, lesson learned whenever you are using CDN, Understand first what it has
Talk to you all later.